--- a/src/share/vm/opto/loopUnswitch.cpp	Tue Apr 08 12:23:15 2008 -0400
+++ b/src/share/vm/opto/loopUnswitch.cpp	Wed Apr 09 09:25:45 2008 -0700
@@ -49,6 +49,9 @@
 // (ie. clone loop with an invariant test that does not exit the loop)
 bool IdealLoopTree::policy_unswitching( PhaseIdealLoop *phase ) const {
   if( !LoopUnswitching ) {
+    return false;
+  }
+  if (!_head->is_Loop()) {
     return false;
   }
   uint nodes_left = MaxNodeLimit - phase->C->unique();

--- a/src/share/vm/opto/loopopts.cpp	Tue Apr 08 12:23:15 2008 -0400
+++ b/src/share/vm/opto/loopopts.cpp	Wed Apr 09 09:25:45 2008 -0700
@@ -2257,6 +2257,9 @@ bool PhaseIdealLoop::is_valid_clone_loop
 //
 bool PhaseIdealLoop::partial_peel( IdealLoopTree *loop, Node_List &old_new ) {
 
+  if (!loop->_head->is_Loop()) {
+    return false;  }
+
   LoopNode *head  = loop->_head->as_Loop();
 
   if (head->is_partial_peel_loop() || head->partial_peel_has_failed()) {